To me it seems like such an easy job:
-Find out if the person is allergic to any medications or has some type of other problems that may be affected
-Calculate how much the patient needs in order to make it through surgery
-Inject medication. Done
Heck, when I had surgery the anesthesiologist asked me if I wanted a shot in the spine which would allow me to wakeup without being groggy, or if I wanted a full blown knockout punch. He explained all the side effects. I was starting to get nervous so I told the guy "You are the doctor, why don't you decide"
Bottom line: Compared to a regular doctor or surgeon, anesthesiology seems like a joke